JP7400519B2 - liquid discharge head - Google Patents

Description

The present invention relates to a liquid ejection head that includes a plurality of individual channels and first and second common channels.

Patent Document 1 (FIGS. 5 to 7) describes a plurality of ejectors (individual flow paths) arranged in the Y direction, and a common supply path tributary (first common flow path) extending in the Y direction and communicating with the plurality of ejectors. An inkjet recording head (liquid ejection head) is shown having a common discharge channel branch (a second common flow channel) and a common discharge channel branch (second common flow channel). Each ejector includes a nozzle, a pressure chamber, a passage (connection passage) that connects the pressure chamber and the nozzle, a supply passage (first communication passage) that communicates the pressure chamber and a branch of the common supply passage, and a passage. and a discharge path (second communication flow path) that communicates with the common discharge path tributary.

Japanese Patent Application Publication No. 2008-290292

In Patent Document 1 (FIGS. 6 and 7), a passage (connection passage) that connects a pressure chamber and a nozzle extends perpendicularly to a discharge passage (second communication passage). In this case, at the boundary between the connection channel and the second communication channel, the direction of the liquid flow vector changes suddenly, causing a speed difference, which tends to cause stagnation and accumulation of bubbles.

An object of the present invention is to provide a liquid ejection head that can suppress stagnation and bubble accumulation at the boundary between a connection channel and a second communication channel.

A liquid ejection head according to the present invention includes a plurality of individual flow paths arranged in a first direction, and a first common flow path and a second common flow path each extending in the first direction and communicating with the plurality of individual flow paths. each of the plurality of individual channels has a nozzle, a pressure chamber, a connecting channel having one end connected to the pressure chamber and the other end connected to the nozzle, and the first common channel. a first communication flow path having one end communicating with the flow path and another end communicating with the pressure chamber; and a second communication flow path having one end communicating with the connection flow path and the other end communicating with the second common flow path. a plurality of nozzles are formed on a nozzle surface along the first direction, and a plurality of nozzles are formed on a nozzle surface extending in the first direction, and a plurality of nozzles are formed on a first surface perpendicular to the first direction, from the one end of the connecting flow path to the a first vector directed toward the other end, the first vector ending at the other end of the connection flow path; and a second vector directed from the one end to the other end of the second communication flow path, the vector A first angle formed with a second vector starting from the one end of the two-way communication channel is less than 90°, and the first angle between the first vector and the second vector is on a second surface parallel to the nozzle surface. It is characterized in that the second angle formed is less than 90°.

According to the present invention, it is possible to suppress stagnation and accumulation of air bubbles at the boundary between the connection channel and the second communication channel.

1 is a plan view of a printer 100 including a head 1 according to a first embodiment of the present invention. FIG. 1 is a plan view of the head 1. FIG. 3 is a sectional view of the head 1 taken along line III-III in FIG. 2. FIG. FIG. 2 is a plan view of a head 201 according to a second embodiment of the invention. 5 is a cross-sectional view of the head 201 taken along line VV in FIG. 4. FIG. FIG. 3 is a plan view of a head 301 according to a third embodiment of the present invention. 7 is a cross-sectional view of the head 301 taken along line VII-VII in FIG. 6. FIG. FIG. 4 is a plan view of a head 401 according to a fourth embodiment of the present invention.

<First embodiment>
First, the overall configuration of a printer 100 including a head 1 according to a first embodiment of the present invention will be described.

The x direction, y direction, and z direction are orthogonal to each other and correspond to the "first direction," "third direction," and "second direction" of the present invention, respectively. In this embodiment, the z direction is a vertical direction, one direction in the z direction (on the front side of the paper in FIG. 1) is upward, and the other direction in the z direction (on the back side in the paper in FIG. 1) is downward.

As shown in FIG. 1, the printer 100 includes a head unit 1x including four heads 1, a platen 3, a transport mechanism 4, and a control section 5.

The head unit 1x is elongated in the x direction and is of a line type that ejects ink onto the paper 9 in a fixed position. The four heads 1 are each elongated in the x direction, and are arranged in a staggered manner in the x direction.

The platen 3 is a plate-shaped member disposed on the other side of the head unit 1x in the z direction. A sheet of paper 9 is supported on one surface (ie, the upper surface) of the platen 3 in the z direction.

The transport mechanism 4 includes two pairs of rollers 41, 41 that sandwich the head unit 1x and platen 3 in the y direction, and a transport motor (not shown) that rotates the pair of rollers 41, 42. When the transport motor is driven under the control of the control unit 5, the pair of rollers 41 and 42 rotates while holding the paper 9 between them, and the paper 9 is transported in the transport direction. The transport direction is a direction along the y direction, and is a direction from one side of the y direction (upper side of FIG. 1) to the other side (lower side of FIG. 1).

The control unit 5 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The ROM stores programs and data for the CPU to perform various controls. The RAM temporarily stores data used when the CPU executes a program. The CPU stores data in the ROM and RAM based on a recording command (including image data) input from an external device (such as a personal computer) or an input unit (switches and buttons provided on the outer surface of the casing of the printer 100). According to the stored programs and data, the driver IC and transport motor (both not shown) of each head 1 are controlled to record an image on the paper 9.

Next, the configuration of the head 1 will be specifically explained.

The head 1 includes a flow path unit 11 and an actuator unit 12, as shown in FIG.

The channel unit 11 is composed of 15 plates 11a to 11o stacked in the z direction and bonded to each other. Each of the plates 11a to 11o is formed with through holes and recesses that constitute flow paths. The flow path includes a plurality of individual flow paths 20, a supply flow path 31, and a return flow path 32.

The plurality of individual channels 20 are arranged in the x direction, as shown in FIG.

The supply channel 31 and the return channel 32 correspond to the "first common channel" and "second common channel" of the present invention, respectively, and extend in the x direction and communicate with the plurality of individual channels 20. ing.

In this embodiment, the supply flow path 31 and the return flow path 32 are lined up in the z direction, as shown in FIGS. 2 and 3. The supply channel 31 and the return channel 32 have substantially the same length in the x direction, the length in the y direction, and the length in the z direction.

The supply flow path 31 and the return flow path 32 communicate with a sub-tank (not shown) through openings 31x and 32x provided at one end in the x direction (the upper end in FIG. 2), respectively. The supply flow path 31 and the return flow path 32 are connected to each other at a connecting portion 33 provided at the other end in the x direction (lower end in FIG. 2).

The opening 31x corresponds to the "inlet of the first common flow path" in the present invention. The opening 32x corresponds to the "outlet of the second common flow path" in the present invention. The connecting portion 33 corresponds to the "outlet of the first common flow path" and "inlet of the second common flow path" in the present invention, and is spaced apart from the openings 31x and 32x in the x direction.

The sub tank communicates with the main tank that stores ink, and stores the ink supplied from the main tank. The ink in the sub-tank flows into the supply channel 31 from the opening 31x by driving a pump (not shown) under the control of the control unit 5. The ink that has flowed into the supply channel 31 is supplied to each individual channel 20 while moving within the supply channel 31 from one end (upper end in FIG. 2) to the other end (lower end in FIG. 2) in the x direction. Ru. The ink that has reached the other end of the supply channel 31 in the x direction (lower end in FIG. 2), that is, the connecting portion 33, and the ink that has flowed out from each individual channel 20 flows into the return channel 32. The ink that has flowed into the return flow path 32 moves from the other end (lower end in FIG. 2) in the x direction toward one end (upper end in FIG. 2) within the return flow path 32, and is returned to the sub tank via the opening 32x. .

As shown in FIG. 3, the supply channel 31 is composed of a recess formed in the lower surface of the plate 11c and through holes formed in the plates 11d to 11g. The return flow path 32 is composed of a recess formed in the lower surface of the plate 11i, through holes formed in the plates 11j to 11l, and a recess formed in the upper surface of the plate 11m. A damper chamber 35 is provided between the supply channel 31 and the return channel 32 in the z direction. The damper chamber 35 is constituted by a recess formed in the lower surface of the plate 11h.

As shown in FIG. 3, each individual flow path 20 communicates the nozzle 21, the pressure chamber 22, the connection flow path 23 connecting the nozzle 21 and the pressure chamber 22, and the pressure chamber 22 and the supply flow path 31. and an outflow channel 25 that communicates the connecting channel 23 and the return channel 32. The inflow channel 24 and the outflow channel 25 have a width smaller than the width (length in the x direction) of the pressure chamber 22, and function as a throttle. The inflow channel 24 and the outflow channel 25 correspond to the "first communication channel" and "second communication channel" of the present invention, respectively.

The nozzle 21 is constituted by a through hole formed in the plate 11o, and is open to the other surface (ie, the lower surface) 11x of the channel unit 11 in the z direction. The lower surface 11x corresponds to the "nozzle surface" of the present invention, and is a surface perpendicular to the z direction and along the x and y directions. A plurality of nozzles 21 are formed on the lower surface 11x.

The pressure chamber 22 is constituted by a through hole formed in the plate 11a, and is open to one surface (ie, the upper surface) of the flow path unit 11 in the z direction.

The connection channel 23 is a columnar channel extending downward from one end of the pressure chamber 22 in the y direction, and is composed of through holes formed in the plates 11b to 11n. The nozzle 21 is arranged directly below the connection channel 23.

The connection flow path 23 has one end 23 a connected to the pressure chamber 22 and the other end 23 b connected to the nozzle 21 . One end 23a is connected to the lower surface of the pressure chamber 22. The other end 23b is connected to the upper surface of the nozzle 21.

The inflow channel 24 has one end 24 a connected to the supply channel 31 and the other end 24 b connected to the pressure chamber 22 . One end 24a is connected to the upper surface of the supply channel 31. The other end 24b is connected to the lower surface of the pressure chamber 22.

The outflow channel 25 has one end 25 a connected to the connection channel 23 and the other end 25 b connected to the return channel 32 . One end 25a is connected to the side surface of the connection channel 23. The other end 25b is connected to the lower surface of the return flow path 32.

In addition to the connecting portion 33, one end 24a of the inflow channel 24 also corresponds to the "outlet of the first common channel" in the present invention. In addition to the connecting portion 33, the other end 25b of the outflow channel 25 also corresponds to the "inlet of the second common channel" in the present invention. These one end 24a and the other end 25b are spaced apart from the openings 31x and 32x in the x direction.

Ink passing through the supply channel 31 is supplied to each individual channel 20 from one end 24a of the inflow channel 24, as shown by arrows in FIG. The ink flows into the pressure chamber 22 through the inflow channel 24, moves approximately horizontally within the pressure chamber 22, and flows into the connection channel 23. The ink moves downward through the connection channel 23, part of it is ejected from the nozzle 21, and the rest passes through the outflow channel 25 and flows out from the other end 25b of the outflow channel 25 to the return channel 32. .

By circulating the ink between the sub-tank and the channel unit 11 in this way, air bubbles can be discharged from the supply channel 31 and the return channel 32 formed in the channel unit 11, as well as the individual channels 20. Ink thickening prevention is achieved.

Here, as shown in FIG. 3, the connecting channel 23 extends not in a direction parallel to the z-direction but in a direction oblique to the z-direction (a direction intersecting the y-direction and the z-direction). The outflow channel 25 extends parallel to the y direction. In the yz plane (the "first surface" of the present invention), the first vector V1 (a vector that goes from one end 23a of the connection channel 23 to the other end 23b, and whose end point is the other end 23b of the connection channel 23) ) and the second vector V2 (a vector directed from one end 25a of the outflow channel 25 to the other end 25b, and whose starting point is the one end 25a of the outflow channel 25) is 90°. less than

Moreover, as shown in FIG. 2, the connection channel 23 extends not in a direction parallel to the y direction but in a direction inclined to the y direction (a direction intersecting the x direction and the y direction). Like the connection channel 23, the outflow channel 25 also extends not in a direction parallel to the y direction but in a direction inclined to the y direction (a direction intersecting the x direction and the y direction). In the xy plane (the "second surface" of the present invention), the first vector V1 and the second vector V2 are parallel to each other (that is, the second angle θ2 formed by these vectors V1 and V2 is 0° ).

Like the outflow channel 25, the inflow channel 24 also extends not in a direction parallel to the y direction but in a direction inclined to the y direction (a direction intersecting the x direction and the y direction). In the xy plane, the inflow channel 24 and the outflow channel 25 are arranged parallel to each other.

The second vector V2 is directed from the connecting portion 33 serving as the inlet of the return flow path 32 and the other end 25b of the outflow flow path 25 to the return flow path along the flow direction of ink in the return flow path 32 (that is, along the x direction). includes a component of the third vector V3) directed toward the opening 32x, which is the exit of the third vector V3). In the xy plane, the third angle θ3 between the second vector V2 and the third vector V3 is greater than or equal to 15° and less than or equal to 45° (approximately 30° in this embodiment).

The fourth vector V4 (vector directed from one end 24a to the other end 24b of the inflow channel 24) is an opening that serves as an inlet of the supply channel 31 along the flow direction of ink in the supply channel 31 (i.e., along the x direction). 31x toward the connecting portion 33 serving as the outlet of the supply channel 31 and one end 24a of the inflow channel 24. In the xy plane, the fourth angle θ4 between the fourth vector V4 and the fifth vector V5 is greater than or equal to 15° and less than or equal to 45° (approximately 30° in this embodiment).

Note that the line III-III in FIG. 2 is parallel to the y direction and does not pass through the inflow channel 24 and the outflow channel 25, but in FIG. (including a flow path 25).

The actuator unit 12 includes, in order from the bottom, a diaphragm 12a, a common electrode 12b, a plurality of piezoelectric bodies 12c, and a plurality of individual electrodes 12d.

The diaphragm 12a and the common electrode 12b are arranged on the upper surface of the flow path unit 11 (the upper surface of the plate 11a), and cover all the pressure chambers 22 formed in the plate 11a. On the other hand, the piezoelectric body 12c and the individual electrode 12d are provided for each pressure chamber 22, and overlap each pressure chamber 22 in the vertical direction.

The common electrode 12b and the plurality of individual electrodes 12d are electrically connected to a driver IC (not shown). The driver IC maintains the potential of the common electrode 12b at the ground potential while changing the potential of the individual electrodes 12d. Specifically, the driver IC generates a drive signal based on a control signal from the control unit 5, and applies the drive signal to the individual electrode 12d. As a result, the potential of the individual electrode 12d changes between the predetermined drive potential and the ground potential. At this time, the portion of the diaphragm 12a and the piezoelectric body 12c sandwiched between the individual electrode 12d and the pressure chamber 22 (actuator 12x) deforms so as to be convex toward the pressure chamber 22. The volume changes, pressure is applied to the ink within the pressure chamber 22, and the ink is ejected from the nozzle 21. The actuator unit 12 has a plurality of actuators 12x corresponding to each pressure chamber 22.

As described above, according to the present embodiment, the first angle θ1 between the first vector V1 and the second vector V2 is less than 90° in the yz plane shown in FIG. The second angle θ2 formed by the first vector V1 and the second vector V2 in the xy plane shown is less than 90°. In this case, compared to the case where the angles θ1 and θ2 are 90° or more, the direction of the ink flow vector changes more gently at the boundary between the connection channel 23 and the outflow channel 25, suppressing the occurrence of a speed difference. be done. Thereby, stagnation and accumulation of bubbles at the boundary between the connection channel 23 and the outflow channel 25 can be suppressed.

The second angle θ2 is 30° or less (0° in this embodiment) (see FIG. 2). In this case, compared to the case where the second angle θ2 exceeds 30°, the direction of the ink flow vector changes more reliably and gently at the boundary between the connection channel 23 and the outflow channel 25. Thereby, a decrease in flow velocity at the boundary portion can be more reliably suppressed.

The second vector V2 is directed from the connecting portion 33 serving as the inlet of the return flow path 32 and the other end 25b of the outflow flow path 25 to the return flow path along the flow direction of ink in the return flow path 32 (that is, along the x direction). 32 (see FIG. 2). When the second vector V2 does not include a component of the third vector V3 (for example, when the third vector V3 is directed from the top to the bottom in FIG. 2), the ink flowing from the outflow channel 25 into the return channel 32 Since the ink tends to flow in the opposite direction to the flow direction of the ink in the return flow path 32, the ink smoothly flows from the outflow flow path 25 to the return flow path 32 and further toward the opening 32x which is the outlet of the return flow path 32. This may cause problems such as the bubbles not being smoothly discharged. In this regard, according to the present embodiment, since the second vector V2 includes a component of the third vector V3, the ink flowing into the return flow path 32 from the outflow flow path 25 is transferred to the opening 32x, which is the outlet of the return flow path 32. It flows smoothly toward the target, promoting the evacuation of air bubbles.

In the xy plane, the third angle θ3 between the second vector V2 and the third vector V3 is greater than or equal to 15° and less than or equal to 45° (approximately 30° in this embodiment) (see FIG. 2). Under the condition that the length of the outflow channel 25 and the position of the other end 25b are not changed, if the third angle θ3 is less than 15 degrees in the xy plane, the connection channel 23 may overlap the return channel 32. It is difficult to adopt a configuration in which the third angle θ3 is less than 15°. In the xy plane, when the third angle θ3 exceeds 45°, the component of the third vector V3 included in the second vector V2 becomes small, and the above effect (the ink flowing from the outflow channel 25 to the return channel 32 It becomes difficult to obtain the effect that the air flows smoothly toward the opening 32x, which is the outlet of the return flow path 32, and the discharge of air bubbles is promoted. In this regard, according to the present embodiment, since the third angle θ3 is 15° or more and 45° or less in the xy plane, it is possible to avoid the situation where the connection flow path 23 overlaps with the return flow path 32, and the above-mentioned effect is achieved. (The effect that the ink flowing into the return channel 32 from the outflow channel 25 flows smoothly toward the opening 32x, which is the outlet of the return channel 32, and the discharge of air bubbles is promoted) can be reliably obtained. .

The fourth vector V4 extends from the opening 31x, which is the inlet of the supply channel 31, to the connecting portion 33, which serves as the outlet of the supply channel 31, along the ink flow direction (that is, the x direction) in the supply channel 31, and It includes a component of the fifth vector V5) directed toward one end 24a of the flow path 24 (see FIG. 2). When the fourth vector V4 does not include a component of the fifth vector V5 (for example, when the fifth vector V5 is directed from the bottom to the top in FIG. 2), the ink flowing into the inflow channel 24 from the supply channel 31 , the ink must flow toward the pressure chamber 22 in a direction opposite to the flow direction of the ink in the supply channel 31, and a sudden change in the flow direction may generate bubbles. In this regard, according to the present embodiment, since the fourth vector V4 includes a component of the fifth vector V5, the ink flowing into the inflow channel 24 from the supply channel 31 smoothly flows toward the pressure chamber 22. The generation of bubbles can be suppressed.

In the xy plane, the fourth angle θ4 between the fourth vector V4 and the fifth vector V5 is greater than or equal to 15° and less than or equal to 45° (approximately 30° in this embodiment) (see FIG. 2). In the xy plane, if the fourth angle θ4 is less than 15°, the inflow channels 24 adjacent to each other in the x direction may overlap each other, so it is difficult to adopt a configuration in which the fourth angle θ4 is less than 15°. In the xy plane, when the fourth angle θ4 exceeds 45°, the component of the fifth vector V5 included in the fourth vector V4 becomes small, and the above effect (the ink flowing into the inflow channel 24 from the supply channel 31 It becomes difficult to obtain the effect of smoothly flowing toward the pressure chamber 22 and suppressing the generation of bubbles. In this regard, according to the present embodiment, since the fourth angle θ4 is 15° or more and 45° or less in the xy plane, it is possible to avoid a situation in which the inflow channels 24 adjacent to each other in the x direction overlap each other, and The above effect (the effect that the ink flowing into the inflow channel 24 from the supply channel 31 flows smoothly toward the pressure chamber 22 and generation of bubbles can be suppressed) can be reliably obtained.

The supply channel 31 and the return channel 32 are arranged in the z direction, and the inflow channel 24 and the outflow channel 25 are arranged parallel to each other in the xy plane (see FIG. 2). In this case, in the xy plane, the fourth vector V4 and the second vector V2 are parallel, and the third angle θ3 and the fourth angle θ4 are the same. As a result, the ink flows smoothly from the supply channel 31 into the inflow channel 24, passes through the pressure chamber 22, and heads from the outflow channel 25 to the return channel 32.

<Second embodiment>
Next, a head 201 according to a second embodiment of the present invention will be described with reference to FIGS. 4 and 5.

In the first embodiment (FIG. 2), in the xy plane, the third angle θ3 between the second vector V2 and the third vector V3, and the fourth angle θ4 between the fourth vector V4 and the fifth vector V5 are , are both approximately 30 degrees, but in the second embodiment (FIG. 4), in the y plane, the third angle θ3 between the second vector V2 and the third vector V3, and the fourth angle θ3 between the fourth vector V4 and the fifth vector The fourth angle θ4 formed with V5 is approximately 60°.

In the xy plane, the first vector V1 and the second vector V2 are parallel to each other as in the first embodiment (that is, the second angle θ2 formed by these vectors V1 and V2 is 0°).

Further, in the first embodiment (FIG. 3), the entire connecting channel 23 is inclined with respect to the z direction, but in the second embodiment (FIG. 5), only the vicinity of the other end 23b of the connecting channel 23 is inclined. is inclined with respect to the z direction.

In the second embodiment (FIG. 5), the connection channel 23 includes an orthogonal portion 23x having one end 23a and extending in the z direction, and an inclined portion 23y connected to the orthogonal portion 23x and having the other end 23b, It includes a slope portion 23y that is sloped with respect to the z direction.

The first vector V1 is a vector that goes from one end 23a of the connection channel 23 to the other end 23b and ends at the other end 23b of the connection channel 23. In the first embodiment (FIG. 3), the first vector V1 is defined by the entire connecting channel 23 (from one end 23a to the other end 23b), but in the second embodiment (FIG. 5), the first vector V1 V1 is defined by the inclined portion 23y of the connection channel 23. In other words, the inclined portion 23y extends in the direction of the first vector V1.

Further, in the yz plane, the first angle θ1 between the first vector V1 and the second vector V2 is smaller than that in the first embodiment (FIG. 3), and is greater than or equal to 45° and less than or equal to 75° (in this embodiment, approximately 60°).

Note that the VV line in FIG. 4 is parallel to the y direction and does not pass through the inflow channel 24 and the outflow channel 25, but in FIG. (including a flow path 25).

As described above, according to the present embodiment, the first angle θ1 is greater than or equal to 45° and less than or equal to 75° (see FIG. 5). When the first angle θ1 is less than 45°, the starting point of the first vector V1 (in this embodiment, the boundary between the orthogonal part 23x and the inclined part 23y; in the first embodiment, the connection flow path 23 and the pressure At the boundary with the chamber 22), the direction of the ink flow vector suddenly changes. If the first angle θ1 exceeds 75°, the effect of moderating the change in the direction of the ink flow vector at the boundary between the connection channel 23 and the outflow channel 25 may be reduced. In this regard, in this embodiment, since the first angle θ1 is 45° or more and 75° or less, each of the above problems can be suppressed.

Furthermore, the connection channel 23 includes an orthogonal section 23x and an inclined section 23y (see FIG. 5). In this case, compared to the case where the entire connecting channel 23 is inclined with respect to the z-direction (see FIG. 3), since the orthogonal portion 23x is not inclined with respect to the z-direction, a space on the side of the orthogonal portion 23x can be secured. . Thereby, the width of the channels 31 and 32 (particularly the supply channel 31) can be increased.

<Third embodiment>
Next, a head 301 according to a third embodiment of the present invention will be described with reference to FIGS. 6 and 7.

In the first embodiment (FIGS. 2 and 3), the supply channel 31 and the return channel 32 are arranged in the z direction, but in the second embodiment (FIGS. 6 and 7), the supply channel 31 and the return channel 32 are arranged in the z direction. The flow paths 32 are arranged in the y direction.

The supply channel 31 communicates with a sub-tank (not shown) via an opening 31x provided at one end in the x direction (upper end in FIG. 6). The return flow path 32 communicates with a sub-tank (not shown) via an opening 32x provided at the other end in the x direction (lower end in FIG. 6). The supply channel 31 and the return channel 32 communicate with each other via a plurality of individual channels 320 arranged in the x direction.

In this embodiment, the opening 31x corresponds to the "inlet of the first common channel" in the present invention, one end 24a of the inflow channel 24 corresponds to the "outlet of the first common channel" in the present invention, and the outflow The other end 25b of the channel 25 corresponds to the "inlet of the second common flow path", and the opening 32x corresponds to the "exit of the second common flow path". The opening 31x is spaced apart from one end 24a of each individual flow path 320 in the x direction. The opening 32x is spaced apart from the other end 25b of each individual flow path 320 in the x direction.

The third vector V3, which runs along the x direction from the other end 25b of the outflow channel 25, which is the inlet of the return channel 32, toward the opening 32x, which is the outlet of the return channel 32, is similar to that in the first embodiment (FIG. ), which is the opposite direction from the top to the bottom of FIG.

As shown in FIG. 6, in the xy plane, the third angle θ3 between the second vector V2 and the third vector V3, and the fourth angle θ4 between the fourth vector V4 and the fifth vector V5 are both approximately 30°, a point where the first vector V1 and second vector V2 are parallel to each other in the xy plane (that is, the second angle θ2 formed by these vectors V1 and V2 is 0°), and As shown in FIG. 7, the first angle θ1 between the first vector V1 and the second vector V2 on the yz plane is less than 90°, similar to the first embodiment.

In this embodiment, as shown in FIG. It extends in the direction that intersects the The directions in which the pressure chamber 22, the connecting channel 23, the inflow channel 24, and the outflow channel 25 extend are parallel to each other. The pressure chamber 22, the connection channel 23, the inflow channel 24, and the outflow channel 25 are arranged on an imaginary straight line L along a direction intersecting the x direction and the y direction.

As described above, according to the present embodiment, the supply channel 31 and the return channel 32 are arranged in the y direction, and in the xy plane, the inflow channel 24 and the outflow channel 25 are arranged in the x direction and the y direction. It is arranged on the virtual straight line L along the direction intersecting the direction. In this case, the ink flows smoothly from the supply channel 31 into the inflow channel 24, passes through the pressure chamber 22, and heads from the outflow channel 25 to the return channel 32.

<Fourth embodiment>
Next, with reference to FIG. 8, a head 401 according to a fourth embodiment of the present invention will be described.

The fourth embodiment (FIG. 8) is a modification of the third embodiment (FIG. 6), in which the third angle θ3 between the second vector V2 and the third vector V3 and the fourth vector The fourth angle θ4 between V4 and the fifth vector V5 is larger than in the third embodiment, and both are approximately 60°.

The points that the first vector V1 and the second vector V2 are parallel to each other in the xy plane (that is, the second angle θ2 formed by these vectors V1 and V2 is 0°) are the same as in the third embodiment. It is.

Further, similarly to the third embodiment, in each individual flow path 420, the pressure chamber 22, the connection flow path 23, the inflow flow path 24, and the outflow flow path 25 are arranged in directions inclined with respect to the y direction (the x direction and the y direction). It extends in the direction that intersects the The directions in which the pressure chamber 22, the connecting channel 23, the inflow channel 24, and the outflow channel 25 extend are parallel to each other. The pressure chamber 22, the connection channel 23, the inflow channel 24, and the outflow channel 25 are arranged on an imaginary straight line L' along a direction intersecting the x direction and the y direction.

As described above, according to the present embodiment, although the angles θ3 and θ4 are different in size, other similar configurations are provided, so that the same effects as in the third embodiment can be obtained.

<Modified example>
Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made within the scope of the claims.

In the embodiments described above (FIGS. 2, 4, 6, and 8), the second angle θ2 is 0°, but it may be less than 90° (preferably 30° or less). That is, the first vector V1 and the second vector V2 may intersect with each other on the xy plane. In this case, for example, the first vector V1 in FIG. 2 may be rotated either clockwise or counterclockwise.

In the embodiments described above (FIGS. 2, 4, 6, and 8), the third angle θ3 and the fourth angle θ4 are the same, but may be different from each other.

In the first embodiment (FIG. 2) and the second embodiment (FIG. 4), the inflow channel 24 and the outflow channel 25 are arranged parallel to each other, but the invention is not limited thereto. For example, the third angle θ3 and the fourth angle θ4 may be different from each other, and the inflow channel 24 and the outflow channel 25 may not be arranged parallel to each other.

In the third embodiment (FIG. 6) and the fourth embodiment (FIG. 8), the inflow channel 24 and the outflow channel 25 are arranged on the virtual straight lines L and L', but the present invention is not limited thereto. For example, the third angle θ3 and the fourth angle θ4 may be different from each other, and the inflow channel 24 and the outflow channel 25 may not be arranged on the virtual straight lines L, L'.

The liquid ejection head is not limited to a line type, and may be a serial type (a type in which liquid is ejected from a nozzle to a target to be ejected while moving in a scanning direction parallel to the nozzle surface).

The target of ejection is not limited to paper, and may be, for example, cloth, a substrate, or the like.

The liquid ejected from the nozzle is not limited to ink, and may be any liquid (for example, a processing liquid that aggregates or precipitates components in the ink).

The present invention is not limited to printers, but can also be applied to facsimiles, copy machines, multifunction devices, and the like. Further, the present invention is also applicable to liquid ejecting devices used for purposes other than image recording (for example, liquid ejecting devices that eject conductive liquid onto a substrate to form a conductive pattern).

1;201;301;401 head (liquid ejection head)
11x Bottom surface (nozzle surface)
20; 220; 320; 420 Individual channel 21 Nozzle 22 Pressure chamber 23 Connection channel 23a One end 23b Other end 23x Orthogonal section 23y Inclined section 24 Inflow channel (first communication channel)
24a One end (outlet of first common flow path)
24b Other end 25 Outflow channel (second communication channel)
25a one end 25b other end (inlet of second common channel)
31 Supply channel (first common channel)
31x opening (inlet of first common flow path)
32 Return flow path (second common flow path)
32x opening (outlet of second common flow path)
33 Connecting portion (outlet of first common flow path, inlet of second common flow path)
L; L' Virtual straight line V1 1st vector V2 2nd vector V3 3rd vector V4 4th vector V5 5th vector θ1 1st angle θ2 2nd angle θ3 3rd angle θ4 4th angle

Claims (10)

a plurality of individual channels arranged in a first direction;
a first common flow path and a second common flow path each extending in the first direction and communicating with the plurality of individual flow paths;
Each of the plurality of individual channels includes a nozzle, a pressure chamber, a connection channel having one end connected to the pressure chamber and another end connected to the nozzle, and one end communicating with the first common channel. and a second communication channel having one end communicating with the connection channel and the other end communicating with the second common channel. including,
A plurality of the nozzles are formed on a nozzle surface along the first direction,
on a first surface perpendicular to the first direction, a first vector directed from the one end to the other end of the connection channel, the first vector having the other end of the connection channel as an end point; A first angle formed with a second vector that is directed from the one end to the other end of the two communicating channels and has a starting point at the one end of the second communicating channel is less than 90°,
A liquid ejection head, wherein a second angle formed by the first vector and the second vector on a second surface parallel to the nozzle surface is less than 90°. The liquid ejection head according to claim 1, wherein the first angle is 45° or more and 75° or less. The liquid ejection head according to claim 1 or 2, wherein the second angle is 30 degrees or less. The connection flow path includes an orthogonal part having the one end and extending in a second direction perpendicular to the nozzle surface, and an inclined part connected to the orthogonal part and having the other end, the inclined part having the one end and extending in the second direction orthogonal to the nozzle surface. The liquid ejection head according to any one of claims 1 to 3, further comprising an inclined portion that is inclined with respect to the direction of the first vector and extends in the direction of the first vector. The second common flow path has an inlet and an outlet spaced apart from the inlet in the first direction,
5. The second vector includes a component of a third vector directed from the inlet to the outlet of the second common flow path along the first direction. The liquid ejection head described in . 6. The liquid ejection head according to claim 5, wherein a third angle between the second vector and the third vector on the second surface is 15 degrees or more and 45 degrees or less. The first common flow path has an inlet and an outlet spaced apart from the inlet in the first direction,
A fourth vector directed from the one end to the other end of the first communication channel includes a component of a fifth vector directed from the inlet to the outlet of the first common channel along the first direction. The liquid ejection head according to claim 5 or 6. 8. The liquid ejection head according to claim 7, wherein a fourth angle between the fourth vector and the fifth vector on the second surface is 15° or more and 45° or less. the first common flow path and the second common flow path are arranged in a second direction perpendicular to the nozzle surface,
Liquid discharge according to any one of claims 5 to 8, wherein the first communication channel and the second communication channel are arranged parallel to each other on the second surface. head. the first common flow path and the second common flow path are arranged in a third direction parallel to the nozzle surface and orthogonal to the first direction;
In the second surface, the first communication channel and the second communication channel are arranged on a virtual straight line along a direction intersecting the first direction and the third direction. The liquid ejection head according to any one of claims 5 to 8.

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